In particular, the invention relates to an aperiodically woven textile displaying a fabric pattern which is produced in such a manner that, in a square starting pattern (Q) which is composed of two weft threads and two warp threads extending at a right angle with respect thereto, a peripheral rotation point is fixed in the middle of one side, three copies of this starting pattern being rotated successively through 90°, 180° and 270° about said rotation point and being positioned in a fan-like manner, one behind another, in order to obtain a composed pattern which is then fixed as the starting pattern for a corresponding, subsequent, fan-like composition of its successive copies that are rotated by 90°, 180° and 270°, in order to, in this way iteratively develop patterns of any desired size from crossing points of threads corresponding to the fabric.
The invention aims to provide aperiodically woven textiles displaying greater permeability to air and greater tear propagation strength, while the strength in the planar structure—maximum tensile strength—remains the same, compared with other aperiodically or periodically woven textiles.
Aperiodically woven textile material is produced following the method of inductive rotation (IR) by means of computer-controlled weaving machines, cf. in particular publication AT 512060 B, wherein mainly the recursive method of the three-step IR method is explained, which method will still be explained in greater detail hereinafter and is of importance regarding the present production of woven fabrics.
In this case, a fabric is produced by machine, wherein a fabric pattern having a square basic pattern corresponding to a crossing point of threads is arranged several times in the fabric. In doing so, the arrangement is accomplished in that, in a square starting pattern Q that is composed of several square basic patterns, i.e., several crossing points of threads, is fixed in the middle of one side, three copies of this starting pattern being rotated successively through 90°, 180° and 270° about said rotation point and being positioned in a fan-like manner one behind another in order to obtain a composite pattern which is then, in turn, fixed as the starting pattern for a subsequent fan-like composition of its copies that have been successively rotated by 90°, 180° and 270°, in order to, in this way, iteratively develop patterns of any desired size from crossing points of threads corresponding to the fabric, wherein the threads in the fabric cross each other aperiodically and asymmetrically above and below. In doing so, the basic patterns are not invariant if rotated. As the result of a precise overlap of the patterns, the three-step IR method produces, simultaneously, a second, parallel, concealed aperiodic and asymmetric fabric pattern, a background fabric pattern that is located exactly behind it and is different from the fabric pattern that is visible in the foreground.
The basic procedure of the three-step IR method is illustrated, in general, in the examples of FIGS. 1A to 1C, wherein, in an exemplary manner, the starting patterns of each iteration are rotated clockwise and the central easternmost point, i.e., the one the farthest to the right, is fixed as the rotation point. FIG. 1A shows a square starting pattern Q that is composed of several (four) square basic patterns, i.e., several crossing points of threads. In accordance with FIG. 1B, this starting pattern Q is copied in successive steps and rotated about the starting pattern position, cf. steps (R(0), R′(0), R″(0), R′″(0)=R1. The thusly obtained complex pattern R(1) can be transformed, in a corresponding manner by copying and rotating, into an even more complex pattern, cf. the steps or iterations of the recursion Q, R(1), R(2), R(3) in FIG. 1C.
The methods of inductive rotation (see publication AT 512060 B) include recursions, wherein the central easternmost, but also westernmost, southernmost or northernmost, point of the starting patterns is fixed as the rotation point and is rotated clockwise but also counterclockwise.
Publication AT 512060 B discloses as example a starting pattern Q that is composed of four equal thread crossings as shown by FIG. 2. In this starting pattern, all four threads crossings are defined in such a manner that the horizontal thread (weft thread) crosses above and the vertical thread (warp thread) crosses below. In accordance with the three-step IR method the threads in the fabric structure jump aperiodically over up to a maximum of seven threads in an orthogonal manner as shown by FIG. 2A. The woven fabric is characterized by more than four to a maximum of seven threads. The analysis of this fabric structure indeed displays great permeability to air and also tear propagation strength, however, due to the skipping of seven threads, there results a massive reduction of the strength within the planar structure and the tensile strength, respectively.
The invention is based on the critical optimization of fabric structures produced according to the three-step IR method, in view of the strength of the planar structure. To accomplish this, the hereinabove stated textile according to the invention is characterized in that, in the starting pattern (Q), the one weft thread—viewed extending from left to right—first overcrosses one of the warp threads and then undercrosses the other one, and the other weft thread crosses over the two warp threads, as a result of which the threads in the fabric structure of the textile jump aperiodically over one to a maximum of three threads in an orthogonal manner.
Consequently, an increased permeability to air and increased tear propagation strength are achieved while the strength of the planar structure and the maximum tensile strength, respectively, are maintained.
Preferably, an expanded starting pattern is assumed, said pattern being formed by a combination of four such starting patterns as stated hereinabove.
In particular, a highly specific starting pattern Q is formed, said pattern being composed of four thread crossings, wherein the right upper thread crossing is rotated by 90 degrees with respect to the other three thread crossings and, consequently, the vertical thread (warp thread) crosses above and the horizontal thread (weft thread) crosses below, as indicated by FIG. 3. According to the three-step IR method the threads in the fabric structure jump aperiodically over up to a maximum of three threads in an orthogonal manner, as illustrated by FIG. 3A. As a result of this, the strength in the planar structure and the maximum tensile strength, respectively, are maintained despite the aperiodicity and inhomogeneity of the material, as is shown by the results of the tests hereinafter, said tests having been performed by the “Staatliche Versuchsanstalt fuer Textil und Informatik” (national testing center for textile and computer science), cf. table hereinafter. These tests on the textile fabric shown by FIG. 3A, when compared to periodically woven textiles, indicate strikingly greater permeability to air, greater tear propagation strength, however mainly uniform strength in the planar structure and maximum tensile strength, respectively. For example, the results, using the specific starting pattern Q of FIG. 3, display so far overall unknown best textile properties.
The “Staatliche Versuchsanstalt fuer Textil und Informatik” in Vienna (Austria) specifically tested a textile that was aperiodically woven according to the three-step IR method by means of a computer-controlled jacquard weaving machine compliant with EN ISO standards, see test protocol in Table 1 hereinafter. Table 1 identifies this aperiodically woven textile that displays the weaving pattern as shown by FIG. 3A, as the “IR prototype”. With the exemplary use of “Tencel” viscose staple fibers, there was determined, compared to exemplary conventional periodically woven fabrics with crepe weave and twill weave with the same warp and weft densities, a greater tear propagation strength in warp direction, as well as in weft direction. Furthermore, due to the aperiodically occurring loose weaving densities, this test indicated a strikingly greater permeability to air. In doing so, the strength of the planar structure—maximum tensile strength—in warp direction remained approximately the same and even increased slightly in weft direction.
TABLE 1FeatureTest StandardSample 1Sample 2Sample 3Sample 4Sample 5WeaveIRCrepeTwillLinenSatinPrototypeK1/3ZA1/725Wt./unit area (g/m2)EN 12127145145145135155Fiber material, viscose staple fibersTencelTencelTencelTencelTencelYarn count warp (twine)10 tex × 210 tex × 210 tex × 210 tex × 210 tex × 2Yarn count weft (yarn)10 tex10 tex10 tex10 tex10 texWarp density (thrd/cm)4545454545Weft density (thrd/cm)3535352548Air permeabl. (l/(min.dm2))EN ISO 92372551406646190Max tensl str warp dir (daN)EN ISO 13934152152150156150Max tensl str weft dir (daN)EN ISO 1393450.750.249.2HK Elongation warp direction (%)EN ISO 1393415.917.316.218.913.1HK Elongation weft direction (%)EN ISO 1393411.411.09.0Tear propagation str warp dir (N)EN ISO 1393745.536.833.4Tear propagation str weft dir (N)EN ISO 1393763.258.651.4
Furthermore, the tests by the “Staatliche Versuchsanstalt fuer Textil and Informatik” with the use of Tencel twine as the warp thread and polyamide yarn as the weft thread resulted in similar measured results. As can be inferred from Tables 2 and 3 hereinafter, the measurements not only indicated a substantially increased permeability to air and improved tear propagation strength but, above all, also an increased maximum tensile strength and thus better strength in the planar structure.